In this papc-r r',/e dcscribc rhe Rcgisrcr Allocation phas. of an cxpcrimcnbl pLlI cqjnpilcr lor rbc _IBM SystcmB?o. (For an oi,ervicw of th! cntirc cornpilcr scc Cockc ana.ULf-stcitr fll.Ior baclground informadon on oprimizarion. scc ha"tr:-Jiril;, iilh. rlsponsibiuty of this pha$ to maD rhc untimitcd nulnf., of,yrnOlrd" ,"giit'rJ ""r"rJ iD thc… (More)
The recent revelation that the human genome contains only ~30,000 genes underscores the importance of gene regulation in generating organismal diversity. Cis-regulatory DNAs, or enhancers, are short stretches of DNA-300 bp to 1,000 bp in length-that control gene expression. This DNA accounts for a substantial fraction of metazoan genomes, but is largely… (More)
Metazoan genomes contain vast tracts of cis-regulatory DNA that have been identified typically through tedious functional assays. As a result, it has not been possible to uncover a cis-regulatory code that links primary DNA sequences to gene expression patterns. In an initial effort to determine whether coordinately regulated genes share a common "grammar,"… (More)
This paper describes a study of a class of algorithms for the floating-point divide and square root operations, based on the Newton-Raphson iterative method. The two main goals were: (1) Proving the IEEE correctness of these iterative floating-point algorithms, i.e. compliance with the IEEE-754 standard for binary floating-point operations . The focus… (More)
Bioinformatics methods have identified enhancers that mediate restricted expression in the Drosophila embryo. However, only a small fraction of the predicted enhancers actually work when tested in vivo. In the present study, co-regulated neurogenic enhancers that are activated by intermediate levels of the Dorsal regulatory gradient are shown to contain… (More)
design jaws as an approach to learning system design techniques that may make possible greater data security. Inputloutput has been found to be involved in most of the weaknesses discovet-ed by a study team in a particular version of the system. Relative design simplicity was found to be the source of greatest protection against penetration eforts. There is… (More)
We present division and square root algorithm for calculations with more bits than are handled by the floating-point hardware. These algorithms avoid the need to multiply two high-precision numbers, speeding up the last iteration by as much as a factor of 10. We also show how to produce the floating-point number closest to the exact result with relatively… (More)
An analysis is given for optimizing run-time range checks in regions of high execution frequency. These optimizations are accomplished using strength reduction, code motion and common subexpression elimination. Test programs, using the above optimizations, are used to illustrate run-time improvements.